Chronic Achilles Tendon Repair: Minimally Invasive Turn-Down Technique with Flexor Hallucis Longus Tendon Transfer

Abstract

Category: Sports; Ankle; Trauma Introduction/Purpose: Chronic achilles tendon injuries present several technical considerations. A reported 20-25% of acute ruptures may be missed and lead to late diagnosis. A commonly faced problem with chronic ruptures is the amount of tendon retraction that occurs, leading to the inability to perform a direct end-to-end repair. Previous studies have demonstrated that central turndown lengthening with addition of flexor hallucis longus (FHL) augmentation can be performed with good results, although it has been associated with post-surgical wound complications and infection. The following description is a turndown technique with FHL tendon transfer augmentation for chronic achilles rupture that allows increased fixation with a tendon to bone construct, accomplished with a minimally invasive approach. Methods: Dissection is made down to the Achilles rupture site. Scar tissue is debrided down to two stable ends. The residual gap is then measured and 2cm is added. This distance is then used to make a proximal incision. Dissection is performed to gastrocnemius tendinous raphe. The central third of this segment is incised perpendicularly. A quadriceps tendon harvester (Arthrex, Naples, FL) is utilized to cut in an antegrade fashion down the tendon portion percutaneously, leaving a 1-1.5cm of tendon spared distally. The tendon is pulled under and through the distal incision. A percutaneous achilles repair system (PARS, Arthrex, Naples, FL) Jig is used to span proximal tendon. FHL tendon transfer is then completed in usual fashion. Suture tails from proximal tendon are then passed through the distal end. Tension is pulled through the sutures, approximating repair. The suture is loaded onto anchors and secured into the calcaneus under tension. Results: Favorable outcomes have been observed following the 2 patients that have had chronic achilles repair with utilization of this minimally invasive turn-down technique with FHL transfer. At a follow up of at least 6 months, no patient has demonstrated wound dehiscence or breakdown. There have been no reports of re-rupture. All patients have been satisfied with the procedure and their level of returned function. Conclusion: Our method of repair with combination of central turndown procedure and FHL tendon transfer provides a suitable option for improved functional outcomes in the treatment of chronic achilles ruptures while providing a minimally invasive approach and avoiding the need for allograft tissue. By using the quadricep tendon harvester in a subcutaneous fashion, incision length can be reduced by nearly 50%. This technique can be performed with existing technologies and is readily reproducible. Using the tendon to bone fixation along with intra-tendinous shuttling, allows for excellent fixation strength, a knotless construct, and almost complete intra-substance suture placement.